Conventionally, vehicles are fitted with wheel speed sensors, for example, for the purpose of vehicle control, such as ABS (Anti-lock Brake System) or the like. A wheel speed sensor is provided in opposition to a rotor that rotates with a wheel so as to detect the magnetic flux variation due to the rotation of the rotor and output an electrical signal corresponding to the result of the detection. A magnetoelectric transducer that converts an magnetic flux variation to an electrical signal (for example, a Hall IC (integrated circuit)) is used as the wheel speed sensor.
JP 2008-268016A proposes a wheel speed sensor in which an exposed part of the resin covering of the Hall IC is protected from damage due to impingement, adhesion, or the like of solid matter, such as iron powder. The wheel speed sensor described in JP 2008-268016A prevents damage to the resin covering of the Hall IC by securely fitting a metal cover on the resin covering.